Chem CSET Flashcards
Freon
dichlorodifluoromethane
isolated system
there is no exchange of matter or energy
Closed system
allows for change in energy but not matter
What are the adverse effects of photochemical smog
Human health
damage to materials
toxic to plants
atmosphere
what substance can be found at the highest point of a fractionating column during fractional distillation of crude oil
propane
Which molecules require description with resonance structures
we can write two are more lewis structures that differ only in the position of electrons.
What type of EM spectrum is strong evidence for the big band theory
microwave
isotopes
atoms of the same number of protons but different number of neutrons
Same atomic number
atomc mass number
number or protons and neutrons
Principal quantum number
n
energy level or size of an orbital.
larger moving down a group
Ground state
lowest energy possible
Electron energy level
spdf
s = 1 -2
p =1-6
d = 1-10
f = 1-14
photon
electron transition from high to low energy orbital.
the difference in energy released.
weightless particle of electromagnetic radiation
types electromagnetic radiation
heat light UV light x rays transverse wave
atomic spectrum
each transition H electrons make correspond to a different amount of energy and different color is released
Bohr model
a small positive nucleus surrounded by electrons located in a specific energy level
electron configuration
arrangement of electrons.
1s2
Group 1
alkali metals
soft
silvery
react violently with water
group 17
halogens
extremely reactive and poisonous
metals
shiny
conductive of heat and electricity
malleable
ductile
nonmetals
brittle,
dull
poor conductors
have low melting and boiling points
metalloids
has properties of metals and nonmetals
when determining molecular mass by osmotic measurement the molar mass will
be less
atomic radius
1/2 the distance between the nuclei of two bonded atoms
increase moving down and left
electromagnetic radiation
a form of energy that travels through space
ionization energy
the amount of energy required to remove an electron.
Increases moving up and right.
ionized
losing one or more outer electrons
electronegative
ability to attract other electrons.
increasing moving up and right.
cannot be measured directly.
has no unit of measurement
boiling point
increases then decreases across a period
metallic character along the periodic table
increases moving left and down
chemical reactivity
substances change chemically
photoelectric effect
when electrons are released after light is shone onto a metal
maxwell’s wave theory of light
brighter (high intensity) light would lead to higher energy electrons
quanta
quantities
E = hf
h = 6.63 x 10 ^-34
Quantum theory
F= frequency of radiation
quantum number
describe a specific aspect of an electron
angular/azimuthal momentum quantum number
shape of the orbital l S= o p=8 d=88 f = flower
magnetic quantum number
position of the electron m1 S=0 p= -1 to 1 d = -2 to 2 f = -3 to 3
spin quantum number
s
spin of the electron determines properties of the atom
+/- 1/2
properties of gas
expand to fill container
v of gas = v of container
can be compressed
ideal gas
theoretical that follows a set of principles.
KMT
no volume, attractive or repulsive forces
all collisions are elastic
KE is proportional to temperature
kinetic molecular theory
model used to explain behavior of matter.
particles are constantly in motion.
KE is related to temperature.
space between particles is related to the state of matter.
phase change happens when temperature changes significantly.
intermolecular forces
properties of liquid
fluid and can flow
definite volume but not shape
low compressibility
properties of solids
definite volume and shape
little KE
arranged in a packed crystalline structuer.
amorphous solid
doesnt have crystalline structure
hydrogen bonds
occur between polar molecules that contain an O F N atom covalently bonded to a H atom
dipole induced dipole
occur when a polar molecule induces a temporary dipole moment in a neighboring non polar molecule
dipole
separation of charges between two covalently bonded atoms.
dipole dipole
intermolecular forces between polar molecule.
positive side of a polar molecule attracts negative or another
london dispersion forces
noble gases and non polar molecule
creates temporary dipoles
ion dipole force
force between an ion and dipole molecule
intermolecular forces
positive charged poles attracted to the negative charged poles
phase change
transition from one state of matter to another
sublimination
solid to gas
deposition
gas to solid
phase diagram
graph of the physical state of a substance and the temperature and pressure of the substance
phase equalibium lines
where two phases are in equalibrium
triple point
point where the temperature and pressure conditions are right for all three states to exist together at equilibrium
critical point
gas and liquid states are identical and the substance is in one phase
supercritical fluid
state where the gas and liquid phase of a substance are indistinguishable
dipole moment
overall unequal distribution of electrons across the entire molecule
non polar molecule
even charge distribution and no dipole moment
polar molecule
uneven distribution charge and dipole moment
macromolecule
huge molecules made up of smaller subunits called monomers.
organic macrmolecules
huge molecules that included C and found in living things
inorganic macromolecule
huge molecule not found in living things.
C to F
5/9 (F-32)
Kelvin scale
absolut scale
K
0 is the absolute lowest
K = C + 273
pressure
psi
atm
mmHg
1 atm = 14.7 psi = 760 mmHg
daltons law of partial presures
total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of each individual gas
Pn + Po = Ptotal
diffustion
movement of 1 substance through another
high to low concentration
effustion
gas particles exit through tiny holes in a container
graham’s law
effusion rate of a gas is inversely proportional to the sqr root of its molecular mass.
used to compare the rate of two different gasses at equilibrium.
speed A / speed B = sqr root (mass B/massA)
standard pressure
1 atm = 760 mmHg = 14.7 psi
standard temperature
0 C = 273 K
Avogadro’s number
- 02 x 10 23 amu = 1 mole
1. 2 x 10 ^-7 XRCD
mole
you have 6.02 x 10 ^23 of something
avogadros law
relationship between the number of particles (n) and the volume of a a gas.
V1/ n1 = V2/ne
1 mole of an ideal gas at STP takes up
22.4 L
Boyles law
temperature is held constant the pressure of a gas increases as volume decreases
P1(V1) = P2(V2)
charles law
if pressure is held constant. as the gas is heated its volume will increase
v1/T1 = V2/T2
T must be Kelvin
Gay-lussac’s law
volume of a container is held constant as the temperature increase, the pressure inside the container increases
P1/T1 = P2/T2
T must be kelvin
ideal gas law
relates the temperature, pressure, number of moles and volume of any gas,
PV = nRT
PV = nRT
P = pressure V = volume n = number of moles R = .08216 atm/molK T = Temperature
solvent
dissolves solutes
miscible
liquid dissovles easily in another
immiscible
liquid doesnt dissolve easily in another
ionic compound
compound held together by ionic bonds
formed by transfer of electrons
polar covalent
atoms held together by valence electrons shared between them
nonpolar covalent
valence electrons are shared equally and are no changes in the molecule
Molarity
moles of solute / L of solution
M
molality
mole solute / kg solvent
m
mass percentage
percent by mass of the solute in the solution
{mass solute / mass solution) x 100%
concentration
amount of a substance in a given quantity in a solution
M1V1 = M2V2
Stoichiometry given to unknown
SOLUBILITY
AMOUNT OF SOLUTE NEEDED TO FORM A SATURATED SOLUTION AT A SPECIFIC TEMPERATURE AND SOLVENT AMOUNT.
polarity
unequal sharing of electrons
factors that influence the rate of solution
amount of solute already dissolved.
temperature
pressure and nature
empirical formula
shows the kind and proportions of atoms in substance in simplest form
chemical formula
shorthand of writing a substance by using chemical symbols and number subscripts with the exact numbers of atoms.
Determine percent composition of compounds
write formula.
use formula to determine molar mass.
use molar mass to determine mass percentage of each element.
determine the empirical formula
- find percent composition.
- determine mass composition.
- determine composition in moles.
- find smallest whole number ratio of atoms.
dissolution
dissolving a substance
like dissolves like
calculate frequency
speed of light = frequency x wavelength
pure substance
cannot be separated
homogeneous mixture
unform throughout
solution
alloy
heterogeneous mixture
not uniform throughout
different components can be seen
separating mixtures
manually, dissolving evaporation distillation magnetism filtration crystallization
chromatography
capillary action
retention factor
Rf
distance dye traveled compared to the total distance the solvent traveled
conjugate acid
acid forms when a base gains a proton
conjugate base
formed when an acid loses protons
Acidity Constant
Ka = [H+] [A-] / [HA]
calculating pH of a solution
-log[H3O+]
Must be in molarity
logarithmic
buffer
solution whose pH will not change much when small amounts of acid or base are added to it.
titration
a solution of known properties is used to analyze the properties of an unknown solution
- balanced equation
- V1M1/n1 =V2M2/n2
equivalence point
the amount of H ions and OH ions are equal and pH = 7
where titration stops
indicator solution
chemical that changes color when a specific pH range
Heat transfer
Delta heat = specific heat (m) (delta T)
titration curve
graph of PH vs volume of titration added
determine the unknown substance concentration
[H+][VH+] = [OH-][VOH-]
- gather information
- set up and fill in equation
- calculate
determine pH during titration
- determine mol of each reactant
- determine which reactant is in excess
- calculate pH based on concentration of the excess reactants
titrant
solution of known properties
pH during weak acid and strong base titration
- determine number of moles of each reactant
- determine reactant excess
- use stoichiometry and Ka/b values to determine acid concentration and pH
- rice table
b. write equilibrium expression for dissociation of acid.
c. plug and solve
Arrhenius equation
K = A e ^(-Ea/RT) A= frequency factor e = exponential factor Ea= activation energy J/mol R = 8.314
ln K = -EA/RT + Ln A
Arrhenius acid
produce hydrogen ions
Arrhenius bases
produces hydroxide ions in water
Bronsted Lowry acid
only substance that can donate a proton
bronsted lowry base
substance that accepts protons
Kw
self ionization of H2O
[H3O+][OH-] = 1 x 10 -14
lewis acid
substance accepts an electron pair to form a covalent bond
lewis base
substance donates an elections pair to form a covalent bond
lewis acid-base reaction
covalent bond is formed between an electron pair bond donor and acceptor
E = mc2
E=energy
m= mass
c = speed of light = 3 x 10 8
nuclear binding energy
energy required to separate the nucleus into its individual pieces
mass defect
difference in mass between a nucleus and its pieces
products weight less
disintegration energy
energy released during radioactive decay.
- find the difference of products and reactants
- multiply 1 u = 1.66 x 10 -27
- plug into E = mc2
radioactive decay
unstable atomic nucleus decays or turns into a more stable nucleus, relating energy in the form of ionizing particles and radiation
alpha decay
nucleus emits an alpha particle. one with four less particles 4 2 blocked by paper cause cancer
alpha particle
containing two protons and two neutrons
beta decay
when a neutron turns into a proton and an electron is emitted 0 -1 stopped by wood penetrate skin used to date living things
gamma decay
occurs when the nucleus of an atom is very high energy 0 0 contains no mass stopped by lead dangerous
what a change in the chemical structure of a hydrocarbon chain isomers that have a shorter chain are
more volatile
have a lower boiling point
radiocarbon dating
carbon dating
method used to determine the age of organic material by measuring the radioactivity of its carbon content
uranium lead dating
used to find the age of a uranium-containing mineral
1 p
1
atomic number of a proton is 1
1 = mass number
1 = atomic number
nuclear chemistry
field of chemistry that deals with the use of radioactive isotopes and other nuclear reactions
nuclear fusion
two or more atoms fuse together to form a single heavier atom
mass and energy is lost
nuclear fission
a heavier atom splits into smaller pieces
chain reaction
domino effect
nuclear fission
chemical reaction
process where the arrangement of atoms, the way they are connected together, is changed
- particles must come into contact with one another
- particles must be lined up correctly
- particles must collide enough to break their bonds
synthesis reaction
joining together of two reactants, to produce a complex product
decomposition reaction
chemical reaction in which a single compound breaks down into two or more compounds or atoms
single displacement reaction
type of chemical reaction where an element reacts with a compound and takes the place of another element in that compound more reactive replaces a less reactive 1. determine if the reaction will occur 2. determine the products 3. balance the equation
Double displacement reaction
a chemical reaction where two compounds react and the positive ions and the negative ions of the two reactants switch place forming two new compounds
- identify individual ions from the reactants and their charges
- switch the cations and anions
- balance the equation
neutralization reaction
occurs between an acid and a base that forms salt and water
gas formation
two compounds react to form a gaseous product
synthesis reaction
reactants combine to form a new compound
two elements
two compounds
compound and element
aqueous
dissolved in water
diatomic molecules
molecules that are composed of two atoms of the same element
H, N, O, F, Cl, Br, I
law of conservation of energy
energy is neither created nor destroyed
exothermic reaction
system releases heat and the surroundings heat up
-
endothermic reaction
system gains heat as the surrounding cool down.
energy is absorbed
(+)
vaporization
enthalpy change
amount of energy as heat that is lost or gained by a system
Delta H = (sum of enthalpies of products) - (sum of enthalpies of reactants)
reaction rate
change in concentration of reactants or products over time
- number of particles
- temperature
- pressure
- catalyst
- size
reaction rate of disappearance
-delta(element) / time
reaction rate of appearance
delta(element) / time
effective collision
- molecules collide with enough energy to break bonds.
2. collide with a favorable orientation
activation energy
minimum amount of energy it takes to start a chemical reaction
activated complex
unstable state what is between the reactants and the products in a chemical reaction
collision theory
helps scientists make predictions about how fast chemical reactions occur
related to the number of successful collisions.
only for gases
chemical equilibrium
when the rate of the forward reaction equals the rate of the reverse reaction and the concentrations of the products and reactants are unchanged
Equilibrium constant
K = [Cx x Dy] / [An x Bm]
only gas and aqueous elements
lechatelier’s principle
any change in a substance on one side of the equation in concentration, temperature or pressure results in an equilibrium shift to oppose the change until a new equilibrium is reached
increase in concentration of reactants will make the reaction shift
right
an exothermic reaction the reactants have an increased temperature the reaction will shift
left
if there is an increase of pressure on the reactants then the reaction will shift
right
reaction quotient
Q = [C]c [D]d / [A]a [B]b determines the direction in which the reaction is moving Q>K right Q=K equilibrium Q < K left
Gibbs free energy
G = H - TS
H= enthalpy
S= entropy
predicts whether a chemical reaction will occur spontaneously
the energy available to do work in chemical reactions.
chemical is measure in reference to another chemical state that is assigned a gibbs free energy of 1
spontaneous reactions
happen without the need of any input of energy
gibbs free energy and spontaneous reactions
delta G = Gf -Gi = Delta H - T(delta S)
Entropy
S
particles spread out more
THird law of thermodynamics
covalent bonds
atoms share elections
strongest
ionic bond
electrons are transferred between atoms of opposite charge
electron sea model
metallic bonding where electrons float free in a sea of electrons around metal atoms
metallic bonding
chemical bonding that takes place from the attraction of metal atoms and the surrounding sea of electrons
structural formula
shows the location of atoms relative to one another.
- determine type and number of atoms.
- write lewis dot structure for each
- connect the atoms by electron pair bonds
polyatomic ion lewis dot structure
- sum the number of valence electrons from each atom
- make a skeleton structure by connecting atoms with single bonds
- determine the remaining electrons
- place remaining electrons to satisfy octet
- double bonds if needed
VSEPR theory
shape of the molecule is related to the organization of the central atom’s valence electrons
molecular geometry
linear
trigonal planar
tetrahedral
bent
trigonal pyramidal
1. find lewis dot structure of the molecule
2. locate of central atom, count the number of electron domains
3. identity the number of nonbonding and bonding domains
4. compare to chart
molar mass
the sum of the total mass in grams of all the atoms that make up a mole of a particular molecule
grams / mole
finding molar mass of a compound
- find the atomic masses of each element
- count how many atoms there are for each element
- find molar mass
calculating number of grams using molar mass
number of moles x molar mass
stoichiometry
study of chemical quantities consumed or produced in a chemical reaction
mole ratio
ratio of moles of one substance to the moles of another substance in a balanced equation
mole to mole calculation
moles of given (moles desired/ moles given ratio) =moles desiered
moles to mass calculations
moles A (mole ration of B / A) (molar mass B) = mass B
mass to moles calculations
mass A (1 / molar mass A)(mole ration B /A) = moles B
mass to mass calculation
mass A (1/molar mass A)(mole ration B/A)(mass B/1) = mass B
molar volume
at STP one more of any gas will fill t 22.4 liters
stoichiometry of gases
- balance the equation
- find the moles of the reactants
- use mole ration to find products made
- convert to desired units
limiting reactant
used up first
excess reactant
substance that is in excess
finding the limiting reactant
- layout givens
- change mass to moles
- multiply a reactant with the mole ratio
determine the amount of product made from the limiting reactant
limiting reactant (mole ration product / limiting reactant)(molar mass product)
theoretical yield
maximum amount of product that can be made from the amount of reactant
- changes to moles
- mole ratio product /reactant
- change product to mass
percent yield
actual yield / theoretical yield (100%)
oxidation number
number assigned to atoms in molecules to show the general distribution of electrons
- if electrons are shared, they belong to the more electronegative atom
- pure elements = 0
- a binary compound the more electronegative element receive oxidation number equal to the negative charge it would have if it were an anion. the less electronegative element receives an oxidation number if it were a cation
- fluorine = -1
- oxygen = - 2 except H2O -1, OF2 is + 2
- Hydrogen = +1 or -1 when combined with metals
- the sum in neutral compound is 0
- sum of polyatomic ions is equal to the charge on the ion
- monatomic ion is equal to the charge of the ion
oxidizing agent
substance that causes the oxidation in another substance
reducing agent
substance that causes another substance to reduce
loses electrons
BIH3 is the strongest
increase down a group
balancing a redox reaction
- write unbalanced equation in ionic form excluding spectator ions.
- give each atom an oxidation number
- write and balance the half reactions
- balance oxygen by adding water
- balance hydrogen by adding hydronium
- make electrons equal and combine the half reactions q
oxidation reaction
reactions that takes an electron
when an element is reduced it
gains electrons
single bonds
type of covalent bond formed from the sharing of two electrons between two atoms
double bonds
type of covalent bond where four electrons are shared between two atoms
triple bond
type of covalent bond where six electrons are shared between two atoms
functional group
an atom or group of atoms that is responsible for a particular chemical property of an organic compound
alcohol
contains one or more hydroxyl groups
R - OH
Higher boiling point due to H bonds between molecules
hydrocarbon
compound made of only carbon and hydrogen
alkyl halide
compound with a halogen atom
takes place of one or more hydrogens in a hydrocarbon
R-X
ketone
the carbon of a carbonyl group share bonds with two other carbons
R - CO -R
aldehyde
carbon of the carbonyl group share a bond with at least one hydrogen
R - CHO
ether
oxygen is bonded to two carbons
R - O - R
carboxylic acid
carboxyl group
R - COOH
hydroxyl group
OH
amine group
NH4
R - N
carbonyl group
C=O
carboxylic acid
OH-C=O
ester group
OR - C =O
polymerization
product is produced with repeating units
addition reaction
two molecules combine together
cracking
breaking up of big hydrocarbons into smaller pieces
redox reaction
where a reduction and oxidation occur
esterification reaction
alcohol combines with carboxylic acid to form an ester and water
fermentation
process of turning a sugar into alcohols, gases or acids
saturated hydrocarbons
have as many hydrogen atoms as possible attached to every carbon
aliphatic hydrocarbons
compounds of hydrogen and carbon that do not contain benzene rings
alkanes
linear
compounds that are made of varying numbers of carbon atoms that are all saturated with hydrogen atoms
cycloalkanes
alkane that contain a carbon ring
alkenes
have at least one double bond between carbon atoms
Eth–
alkynes
have at least one triple bond between carbon atoms
alkenynes
have both double and triple bonds
arenes
aromatic hydrocarbons
have at least one benzene ring
benzene ring
a ring of 6 carbon atoms with three double bonds
aromatic compound
any compound with a benzene ring
isomers
different forms of the same compound.
functional group is placed at a different location.
carbohydrates
sugars
contain ether, hydroxyl groups
polysaccharide
large sugar
when counting carbons in a carbohydrate
- find carbon attached to 2 oxygen atoms
2. then count carbons it is attached to
monosaccharide
single sugar
disaccharide
sugar molecule containing two monosaccharides
glycosidic linkage
bond between sugars
lipids
biological molecules that are insoluble in water but soluble in nonpolar solvents
saturated fats
triglycerides that have no double bonds in their carboxylic acid chains
unsaturated fats
triglycerides that have double bonds in their carboxylic acid chains
trans fats
synthetic
triglycerides that have trans double bonds in their carboxylic acid chains
peptide body
covalent bond that holds amino acids together
carbonyl and amino nitrogen group
enzymes
proteins that enable chemical reactions in our bodies
decrease activation barrier
the amount of kinetic energy of an object is dependent on
mass
speed
Kinetic energy
KE = 1/2 mas (velocity)sqr
energy transformation
process of changing energy from one form to another
chemical energy
from chemical reaction
heat energy
from thermal reactions
electrical energy
from charged particles
gravitational potential energy
energy stored by an object because of its location above the ground
elastic potential energy
energy stored by an object that can be stretched or compressed
nuclear energy
energy stored in the nucleus of an atom
fission
fusion
internal energy of the system
total kinetic energy of the particles and the potential energy of the particles
potential energy is measured by
the phase of an object
1 food calories =
1,000 calories
4.184 J
heat of fusion
heat energy/mass
Hf = m/q
heat of vaporization
amount of energy required to turn a liquid into a gas at its boiling point
Hv = q/m
hess’s law
measure enthalpy change of a chemical reaction
adding or subtracting chemical reactions with the same products or reactants.
what ever happens to one side you must do to the other
thermochecmical equations
shows the enthalpy change going from reactants to products
calorie
amount of energy required to raise the temperature of one gram of water by 1 C
specific heat capacity
amount of energy required to change the temperature of one gram of a substance by 1 C Q = sm deltaT Q= energy s= specific heat capacity T = Celcius
S = q/m delta T
heating and cooling curves
line graph that shows the phase changes a given substance undergoes with increasing or decreasing temperature
bond enthalpy
energy needed to break a particular bond in a gaseous compound
kJ/mol
bond enthalpy values
value of energy required to break a particular chemical bond at 298K (25 C)
radiation
transmission of energy from a body in the form of waves or particles
nonionizing radiation
encompasses the electromagnetic spectrum from low energy ultraviolet light
nuclear fusion
ionization radiation
higher frequencies of the electromagnetic spectrum
nuclear fission
radioactive decay
Electronegativity
increased up and right
During titration of adding acid to a base, a few drops of acid are added into the solution after the endpoint. How will this affect calculations for the concentration of the base?
It will make the calculations too high. Making the base look stronger than it is.
Few drops of water left in a buret that is used to titrate a base into an acid. Will the small amount of water have any effect on the determined value for the concentration of the acid?
Yes, because the water will dilute the base, creating an error.
Calculating pOH
pH =-log [H]
pOH = 14 -pH
Must be molarity
pKa
-logKa
Find pKb from pKa
14 - pKa
to find concentration from pH
10 ^ concentration
parts per million
(g solute / g solution) x 10^6
Erg =
visible waves
Magnetic moment
sqrt (n(n+2))
n= unpared eletrons
Density
g/cm3
What gas is mostly responsible for the greenhouse effect
carbon dioxide
calculate percentage error
actual - measured / acual ) x 100
How do energies of similar bonds compare
consistent
x rays are in the wavelength range of
.01 - 10 nm
Bohr’s atomic model
mvr = nh/2pi N = number of orbits
Coulombs law
ionization energy increases proportionally with the atomic number
Faraday
1 mole of electrons
How does dialysis work
allows the electrolytes to pass through and not solution particles
types of statistical series
Spatial conditional times qualitative quantitative
calculate the molecular mass from vapor pressure
2 (vapor density)
Solubility of alkaline earth metal hydroxides/ oxides
increase down a group
solubility of alkaline earth metal sulfates
increase up a group
Amu of an electron
1/2000
accuracy
how close a measurement is to the true value
precision
how close repeated measurements are to each other
